Gavin Williamson was sacked by the Prime Minister as Defence Secretary on Wednesday evening.
The decision, as also explained in a letter sent by Theresa May to the former Defence Secretary, is linked to the unauthorised disclosure of information from a National Security Council meeting last week.
With more and more calls for a police investigation into the scandal mounting among MPs, we look at how a confidential leak took Gavin Williamson down.
On 23 April 2019, a meeting of the National Security Council (NSC), the UK top security body that includes Cabinet ministers, is held.
The following day, on 24 April, in an article published by The Daily Telegraph, information concerning the meeting are published.
The article reports on the Prime Minister agreeing to let the much-criticised Chinese tech brand Huawei develop 5G networks in the UK regardless of security concerns raised by the NSC.
It immediately becomes evident that someone who attended the meeting has shared confidential information with the press.
The response to the leak
The following day, on 25 April, the Labour Party demands that an official investigation is conducted into the leak.
The incident is referred to as "deeply worrying" by Dominic Grieve, Chairman of the Parliamentary Intelligence and Security Committee.
Home Secretary Sajid Javid called it "unacceptable".
A formal inquiry is launched to investigate the leak. It is led by Sir Mark Sedwill, who said he was "deeply unhappy" about what happened.
Both Gavin Williamson and Foreign Secretary Jeremy Hunt publicly deny they are the source of the leak.
On 26 April, ministers are given an ultimatum to confess or deny if those who attended the NSC session were behind the leak.
Sir Mark Sedwill demands that ministers cooperate with his inquiry into the Huawei leak.
There are reports of an "ultimatum" given to ministers to come forward and say whether they were responsible for the disclosure of the information.
On 27 April, personal emails and phones of ministers who attended the NSC meeting and their advisers are requested for checks.
Meanwhile, the Chinese Ambassador to the United Kingdom defends the tech company Huawei.
The following day, on 28 April, Jeremy Hunt confirms that officials are conducting interviews and he has been questioned and is prepared to hand over his phone as part of a leak probe.
The US response
On 29 April, the US issues a warning stating that there can be no degree of safety when a Chinese tech giant is involved in the development of 5G networks in the West.
Its line about Huawei is clear: the Chinese tech giant poses a risk to British citizens and could breach privacy.
On 1 May, it is revealed that Gavin Williamson had a phone conversation with a reporter shortly after the NSC meeting.
The call appears to be between Gavin Williamson and Daily Telegraph journalist Steven Swinford and it ran between 5.31PM until 5.42PM (11 minutes).
Mr Williamson continues claiming his innocence and says he had voluntarily shown the inquiry the call records on his phone.
The same day, Theresa May sacks Gavin Williamson as Defence Secretary.
A Downing Street spokesperson says the Prime Minister has "lost confidence in his ability to serve".
Citing the Official Secrets Act, Labour calls for a police investigation into the case.
Following the dismissal of Mr Williamson as Defence Secretary, on 1 May the role is taken over by Penny Mordaunt.
On 2 May, just over a week since the NSC meeting from which information was leaked, Mr Williamson tweets for the first time since losing his job.
On 3 May, it is reported that Gavin Williamson is considering the possibility of giving a speech.
Foreign Secretary Jeremy Hunt tells the BBC that he hopes Mr Williamson could one day be back at the MOD.